Investigating Biological Rhythms Disruptions Across the Menstrual Cycle in Women with Comorbid Bipolar Disorder and Premenstrual Dysphoric Disorder

Abstract

Introduction: Sleep and biological rhythms have not been investigated in women with comorbid Bipolar and Premenstrual Dysphoric Disorder in the context of the menstrual cycle. We explored whether menstrual cycle phase causes increased disturbances in sleep, biological rhythms and mood symptoms. Additionally, we explored whether these women have worse illness outcome than women diagnosed with either Bipolar or Premenstrual Dysphoric Disorder, and healthy women. Methods: In this post-hoc analysis, participants were split into four groups: those with a Bipolar and comorbid Premenstrual Dysphoric Disorder diagnosis (n = 17, BDPMDD), those with a Bipolar Disorder diagnosis (n = 16, BD), those with a Premenstrual Dysphoric Disorder diagnosis (n = 19, PMDD), and women with no history of psychiatric diagnosis (n = 25, HC). The primary outcome variable was biological rhythm disruption as measured by the Biological Rhythms Interview and Assessment in Neuropsychiatry (BRIAN). The secondary outcome variables were depressive symptoms (Montgomery-Asberg Depression Scale, MADRS; Hamilton Depression Rating Scale, HAMD), manic symptoms (Young Mania Rating Scale, YMRS), and sleep quality (Pittsburgh Sleep Quality Index, PSQI). All variables were collected at both mid-follicular and late-luteal stages of the menstrual cycle. Results: The BDPMDD group did not have significantly higher disruptions in biological rhythms than the BD or PMDD groups at the luteal phase; however, there were significant disruptions and mood symptoms in comparison to the HC group, especially at the follicular stage, which point to markedly higher disruptions in these areas that seem to persist beyond the symptomatic luteal phase. Conclusion and Future Directions: Women diagnosed with a BD and PMDD comorbidity experience a higher illness burden then women diagnosed with either BD or PMDD. A relatively small sample size, not excluding for participants who were taking medications that affect sleep and relying solely on subjective measures of biological rhythms may explain some of the null results. Future studies should employ objective measures of sleep such as actigraphy to complement subjective measures like the BRIAN, as well as recruit a larger sample of participants. More importantly, more studies surrounding this topic must be done in order to create a robust body of evidence that can be used to compare results across studies and identify specific biological rhythms domains that can be targets for treatment.